摘要
目的探讨环6号染色体综合征病例染色体缺失片段和定位于其中的基因与临床表型的关系。方法2013年就诊于北京大学第一医院的2例环6号染色体综合征病例纳入研究。其中病例1孕妇妊娠21^＋1周，因妊娠中期血清学唐氏综合征筛查高风险而行产前诊断，胎儿染色体核型分析结果为46，xY,r（6）[14]／46，XY,r（6；6）[1]／45，XY’-6[15]。病例2为8月龄女性婴儿，发育落后，面部畸形，染色体核型为46，XX，r（6）／47，XX，r（6）×2／46，XX，r（6；6）／45，XX，一6。应用多重连接探针扩增及比较基因组杂交技术检测2例病例6号染色体短臂和长臂末端亚端粒区的缺失情况及基因缺失片段位置及大小，复习相关文献。结果多重连接探针扩增技术确定2例均存在6号染色体短臂和长臂末端亚端粒区缺失。比较基因组杂交技术分析发现：病例1胎儿的6号染色体短臂末端6p25．3～25．2区缺失2．42Mb，主要包含已知的DUSP22、IRF4、EXOC2、FOXC1、FOXF2及FOXQ等基因；长臂末端6q26～27区缺失7．84Mb，主要包含已知的PARK2、PACRG、LOC28596和RPS6KA2等基因。病例2患儿6号染色体短臂末端6p25．3～25．1区缺失5．44Mb，主要包含已知的DUSP22、IRF4、EXOC2、FOXC1、FOXF2、FOXQ及SERPINB6等基因；长臂末端6q27缺失0．16Mb，主要包含PSMB1、TBP及PDCD2等基因。2个病例除表现出“环状染色体综合征”共同特点之生长发育落后外，病例1还合并小脑偏小，病例2合并小头畸形和双眼内斜。结论环6号染色体综合征患者临床特征的差异与染色体区带缺失部位和缺失大小密切相关。
Objective To understand the correlation between chromosome deletion and the phenotypes in cases of ring chromosome 6 syndrome. Methods Two cases of ring chromosome 6 syndrome persented to the Peking University First Hospital in 2013 were studied. Case 1 was a fetus diagnosed as having ring chromosome 6 with karyotype 46, XY, r （ 6 ） [14]/46, XY, r （ 6; 6 ） [1]/45, XY, -6[15] from a pregnant woman who received prenatal examination because of high risk found in serum screening for Down＇s syndrome at 21＋1 weeks of gestation. Case 2 was an eight-month-old female infant with growth retardation and congenital facial anomaly, whose karyotype was 46, XX, r （ 6 ） /47, XX, r （ 6 ） × 2/46, XX, r （ 6; 6 ） /45, XX, -6. Multiplex ligation-dependent probe amplification and array-based comparative genomic hybridization were used to detect the location of chromosome telomeric loss and its size, and the correlation between chromosome deletion and the phenotypes was analyzed by reviewing related literatures. Results Case 1 was confirmed to have short-arm terminal deletions on 6p25.3-25.2 （ 2.42 Mb ） which mainly included DUSP22, IRF4, EXOC2, FOXC1, FOXF2 and FOXQ genes, and long-arm terminal deletions on 6q26-27 （ 7.84 Mb ） mainly included PARK2, PACRG, LOC28596 and RPS6KA2 genes. Case 2 had short-arm terminal deletions on 6p25.3- 25.1 （ 5.44 Mb ） which included DUSP22, IRF4, EXOC2, FOXC1, FOXF2, FOXQ and SERPINB6 genes, and long-arm terminal deletions on 6q27 （ 0.16 Mb ） which included PSMB1, TBP and PDCD2 genes. Except for the growth retardation, the common feature of ＂ring syndrome＂, in both cases, cerebellum hypoplasia was observed in case 1, and microcephaly and esotropia were observed in case 2. Conclusions The difference of phenotypes in patients with a ring chromosome 6 is closely associated with the location and size of the deletion in chromosome 6.
出处
《中华围产医学杂志》
CAS
北大核心
2014年第11期724-728,共5页
Chinese Journal of Perinatal Medicine
关键词
环状染色体
染色体
人
6对
染色体缺失
表型
产前诊断
Ring chromosomes
Chromosomes, human, pair 6
Chromosome deletion
Phenotype
Prenatal diagnosis
